/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package org.dom4j.io;

import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;

import org.dom4j.Document;

import org.xml.sax.InputSource;

/**
 * <p> <code>DocumentInputSource</code> implements a SAX {@link InputSource}for
 * a {@link Document}. </p>
 * 
 * @author <a href="mailto:james.strachan@metastuff.com">James Strachan </a>
 * @version $Revision: 1.2 $
 */
class DocumentInputSource extends InputSource
{
   /** The document source */
   private Document document;

   public DocumentInputSource()
   {
   }

   public DocumentInputSource(Document document)
   {
      this.document = document;
      setSystemId(document.getName());
   }

   // Properties
   // -------------------------------------------------------------------------

   /**
    * DOCUMENT ME!
    * 
    * @return the document which is being used as the SAX {@link InputSource}
    */
   public Document getDocument()
   {
      return document;
   }

   /**
    * Sets the document used as the SAX {@link InputSource}
    * 
    * @param document DOCUMENT ME!
    */
   public void setDocument(Document document)
   {
      this.document = document;
      setSystemId(document.getName());
   }

   // Overloaded methods
   // -------------------------------------------------------------------------

   /**
    * This method is not supported as this source is always a {@linkDocument}
    * instance.
    * 
    * @param characterStream DOCUMENT ME!
    * 
    * @throws UnsupportedOperationException as this method is unsupported
    */
   public void setCharacterStream(Reader characterStream)
      throws UnsupportedOperationException
   {
      throw new UnsupportedOperationException();
   }

   /**
    * Note this method is quite inefficent, it turns the in memory XML tree
    * object model into a single block of text which can then be read by other
    * XML parsers. Should only be used with care.
    * 
    * @return DOCUMENT ME!
    */
   public Reader getCharacterStream()
   {
      try
      {
         StringWriter out = new StringWriter();
         XMLWriter writer = new XMLWriter(out);
         writer.write(document);
         writer.flush();

         return new StringReader(out.toString());
      }
      catch(final IOException e)
      {
         // this should never really happen
         // but for completeness we'll return a Reader
         // with the embedded exception inside it
         return new Reader()
            {
               public int read(char[] ch, int offset, int length)
                  throws IOException
               {
                  throw e;
               }

               public void close() throws IOException
               {
               }
            };
      }
   }
}

/*
 * Redistribution and use of this software and associated documentation
 * ("Software"), with or without modification, are permitted provided that the
 * following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and
 * notices. Redistributions must also contain a copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived
 * from this Software without prior written permission of MetaStuff, Ltd. For
 * written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may
 * "DOM4J" appear in their names without prior written permission of MetaStuff,
 * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
